Question: What do the following two equations represent? $-5x-2y = -1$ $6x-15y = 4$
Explanation: Putting the first equation in $y = mx + b$ form gives: $-5x-2y = -1$ $-2y = 5x-1$ $y = -\dfrac{5}{2}x + \dfrac{1}{2}$ Putting the second equation in $y = mx + b$ form gives: $6x-15y = 4$ $-15y = -6x+4$ $y = \dfrac{2}{5}x - \dfrac{4}{15}$ The slopes are negative inverses of each other, so the lines are perpendicular.